Whatis a Cos 2X? The trigonometric ratios of an angle in a right triangle define the relationship between the angle and the length of its sides. Cosine 2X or Cos 2X is also, one such trigonometrical formula, also known as double angle formula, as it has a double angle in it. Because of this, it is being driven by the expressions for Detailedstep by step solution for cos(x)=sin(1/(2x)) This website uses cookies to ensure you get the best experience. By using this website, you agree to our Cookie Policy. Now that we have derived cos2x = cos 2 x - sin 2 x, we will derive cos2x in terms of tan x. We will use a few trigonometric identities and trigonometric formulas such as cos2x = cos 2 x - sin 2 x, cos 2 x + sin 2 x = 1, and tan x = sin x/ cos x. We have, cos2x = cos 2 x - sin 2 x = (cos 2 x - sin 2 x)/1 = (cos 2 x - sin 2 x)/( cos 2 x + sin 2 x) [Because cos 2 x + sin 2 x = 1]. Divide the cos^2x-sin^2x= -cosx# #cos 2x= cos (- x)# #=> 2x = -x => 3x = 0 ,x = 0# Right this is a definite solution. Lets go back to the equation #2cos^2 x - 1 = - cos x# Bring everything over to one side. Let # cos x = a# #2a^2 + a -1 = 0# Factoring you get #(2a -1)(a + 1) = 0# #2a - 1 = 0# #a = 1/2# Answer(1 of 3): Sin x/cos^2x=2cos x. tan x=2cos^2 x tan x=2/sec^2 x=2/(1+tan^2 x) tan x+tan^3x-2=0 (tanx-1)+(tan^3 x-1)=0 (tanx -1)+(tan x-1)(tan^2 x+tan x+1)=0 (tan Đơngiản biểu thức (Cos^2x-sin^2x)/ (cot^2-tan^2x) -cos^2x. Đơn giản biểu thức (Cos^2x-sin^2x)/ (cot^2-tan^2x) -cos^2x. O L M. Học bài; Hỏi đáp; Kiểm tra; Bài viết Cuộc thi Tin tức. Trợ giúp ĐĂNG NHẬP ĐĂNG KÝ Đăng nhập Đăng ký Takingsquare root on both sides. cosx + sinx = sinx ± √1 - sin 2 x. By using the cofunction or complement identity. cosx = sin (π/2 - x) sinx + cosx = sinx + sin (π/2 - x) Therefore, when asked What is sin x + cos x in terms of sine? then the answer will be sin x + cos x in terms of sine is sinx + sin (π/2 - x). up6diU. \bold{\mathrm{Basic}} \bold{\alpha\beta\gamma} \bold{\mathrm{AB\Gamma}} \bold{\sin\cos} \bold{\ge\div\rightarrow} \bold{\overline{x}\space\mathbb{C}\forall} \bold{\sum\space\int\space\product} \bold{\begin{pmatrix}\square&\square\\\square&\square\end{pmatrix}} \bold{H_{2}O} \square^{2} x^{\square} \sqrt{\square} \nthroot[\msquare]{\square} \frac{\msquare}{\msquare} \log_{\msquare} \pi \theta \infty \int \frac{d}{dx} \ge \le \cdot \div x^{\circ} \square \square f\\circ\g fx \ln e^{\square} \left\square\right^{'} \frac{\partial}{\partial x} \int_{\msquare}^{\msquare} \lim \sum \sin \cos \tan \cot \csc \sec \alpha \beta \gamma \delta \zeta \eta \theta \iota \kappa \lambda \mu \nu \xi \pi \rho \sigma \tau \upsilon \phi \chi \psi \omega A B \Gamma \Delta E Z H \Theta K \Lambda M N \Xi \Pi P \Sigma T \Upsilon \Phi X \Psi \Omega \sin \cos \tan \cot \sec \csc \sinh \cosh \tanh \coth \sech \arcsin \arccos \arctan \arccot \arcsec \arccsc \arcsinh \arccosh \arctanh \arccoth \arcsech \begin{cases}\square\\\square\end{cases} \begin{cases}\square\\\square\\\square\end{cases} = \ne \div \cdot \times \le \ge \square [\square] ▭\\longdivision{▭} \times \twostack{▭}{▭} + \twostack{▭}{▭} - \twostack{▭}{▭} \square! x^{\circ} \rightarrow \lfloor\square\rfloor \lceil\square\rceil \overline{\square} \vec{\square} \in \forall \notin \exist \mathbb{R} \mathbb{C} \mathbb{N} \mathbb{Z} \emptyset \vee \wedge \neg \oplus \cap \cup \square^{c} \subset \subsete \superset \supersete \int \int\int \int\int\int \int_{\square}^{\square} \int_{\square}^{\square}\int_{\square}^{\square} \int_{\square}^{\square}\int_{\square}^{\square}\int_{\square}^{\square} \sum \prod \lim \lim _{x\to \infty } \lim _{x\to 0+} \lim _{x\to 0-} \frac{d}{dx} \frac{d^2}{dx^2} \left\square\right^{'} \left\square\right^{''} \frac{\partial}{\partial x} 2\times2 2\times3 3\times3 3\times2 4\times2 4\times3 4\times4 3\times4 2\times4 5\times5 1\times2 1\times3 1\times4 1\times5 1\times6 2\times1 3\times1 4\times1 5\times1 6\times1 7\times1 \mathrm{Radians} \mathrm{Degrees} \square! % \mathrm{clear} \arcsin \sin \sqrt{\square} 7 8 9 \div \arccos \cos \ln 4 5 6 \times \arctan \tan \log 1 2 3 - \pi e x^{\square} 0 . \bold{=} + Subscribe to verify your answer Subscribe Sign in to save notes Sign in Show Steps Number Line Examples x^{2}-x-6=0 -x+3\gt 2x+1 line\1,\2,\3,\1 fx=x^3 prove\\tan^2x-\sin^2x=\tan^2x\sin^2x \frac{d}{dx}\frac{3x+9}{2-x} \sin^2\theta' \sin120 \lim _{x\to 0}x\ln x \int e^x\cos xdx \int_{0}^{\pi}\sinxdx \sum_{n=0}^{\infty}\frac{3}{2^n} Show More Description Solve problems from Pre Algebra to Calculus step-by-step step-by-step \cos^{2}x-\sin^{2}x en Related Symbolab blog posts Practice, practice, practice Math can be an intimidating subject. Each new topic we learn has symbols and problems we have never seen. The unknowing... Read More Enter a problem Save to Notebook! Sign in cosxsinx = sin2x/2 Explanation So we have cosxsinx If we multiply it by two we have 2cosxsinx Which we can say it's a sum cosxsinx+sinxcosx Which is the double angle formula of the sine cosxsinx+sinxcosx=sin2x But since we multiplied by 2 early on to get to that, we need to divide by two to make the equality, so cosxsinx = sin2x/2 Álgebra Exemplos Problemas populares Álgebra Simplifique cosx^2-sinx^2/cosx-sinx Step 1Como os dois termos são quadrados perfeitos, fatore usando a fórmula da diferença de quadrados, em que e .Step 2Cancele o fator comum de .Toque para ver mais passagens...Cancele o fator por .